Reaming-drill.



Lav/enfer.-

Claizece Ed'zeavdeed,

@NITE CLARENCE EDW. REED, 0F HOUSTON, TEXAS.

REAMING-DRILL.

Specication of Letters Patent. Patented Nov, 12, 1918.

Application led fuly 16, 1917. Serial No. 180,878.

To all whom t may concern: 4

Be it known that I, CLARENCE E. REED, a citizen ofthe United States, and resident of Houston, Texas, have invented certain new and useful Improvements in Reaming- Drills, of which the following is a specification.

My present invention relates to improve-y ments in drills designed more especially for efficiency in boring hard rock and aims to provide a construction which shall be durable and efficient and in which the maincutting action will be secured by terminal rotary cutters while the reaming will be secured by independent cutters properly housed and protected by the drill head.

With these and other objects in view the invention includes the novel features of construction and arrangement and combination of parts hereinafter described and particularly defined by the appended claims, an embodiment of the invention being illustrated in the accompanying drawings, in which,

Figure -1 is aside elevation of a drill head.

Fig. 2 is a transverse vertical section.

Fig. 3 is a similar section at right angles to the section'shown in Fig. 2.

Referring by reference characters to said drawing the numeral 1 indicates the drill head which is preferably of the shape shown and has its upper portion exteriorly screwthreaded for connection with the lower end of the drill stem, (not shown).

This head is provided with water pagsages 1 leading lto the recess orcavity 2 containing the main cutters, and with other water passages 1b leading ,to the cavities or recesses 3 housing the reaming cutters 4. The main cutters are mounted on a transverse shaft 5, which is preferably inserted through a tapered opening in one wall ofthe cavity and held in position by having its threaded end y5n screwed into a correspondingly threaded opening in the other wall, the head of the shaft being provided with a kerf or non-circular recess 5b for the application of a suitable tool to lenable the shaft to be screwed home. -The main cutters may conveniently take the form of two outer cylindrical cutters 6, two inner cylindrical cutters 7, andv two intermediate beveled orl tapered cutters 8', all journaled on the shaft w 5 and having teeth or cutting projections of any approved form. Wear plates or washers9 are preferably interposed between f the outer cutters and the side walls of the recess. y

The shaft/5 is provided with a hollow interior or bore be forming a lubricantchamber from which lubricant reaches the bearing surfaces of the rollers through ports 5d, and the lubricant chamber is closedby a screw plug 5e.

The cavities 3 containing the reaming cutters converge upwardly at such an inclination as to bring the working thrust as nearly as possible perpendicular to the axis of the bearing pins or spindles 10. These bearing pins or shafts arepreferably, like shaft 5, provided with tapered heads 10a at one end and with screw-threaded shanks 10b at the opposite end engaging correspondingly threaded openings in the inner walls of the cavities 3. The shafts 10 may be secured against working out by locking nuts 11.

The reaming cutters 4 are arranged "to trim out the peripheral portion at the bottom of the hole left by the main cutters and also to ream out the sides of the hole to gives sufiicient clearance, the cutting or trimming and reaming actions merging the one into the other, and to this end these cutters are formed'with curved surfaces 4, which begin with a gradual curve at the portion a, the curve gradually increasing or having a shorter radius as the greatest diameter of the cutter is approached.

e The cutters 4 may be provided with teeth of any approved form, and I prefer to mount them on suitable bushings 4x and be'- tween side wear plates or washers 4b. I also provide them with lubricant chambers 4.

What I claim is:

1. A reaming drill comprising a head provided at its lower endl with main cutting means and separate .and distinct reaming cutters housed in pockets on opposite sides of the main cutting means and having portions projecting therefrom, each of said reaming cutters when viewed in cross section presenting a curved edge merging into a fiat face on one side and intoa flattened curve on the other side, thetangent of which uflattened curve is at an acute angle to said flattened face, said reaming cutters being constructed and adapted to cut and ream the side walls of a hole.

2. A reaming drill comprising ahead-pro- Vflattened face, said reaming cutters being arranged to bear upon, to roll against, or toy ream the hole.

. 3. A reaming drill comprising a head provided at its lower end with main cutting means, and having downwardly diverging pockets on each side of said cutting means and open at their lower ends, and

yreamingcutters journaled in said pockets and projecting therefrom, said cutters having teeth on an oval shaped portion with the radiiof the curve gradually decreasing toward the 'center of the drill, the major portion 'of the teeth reaming the hole formed by the drill.

4. A reaming drill comprising a head i provided with apocket, and a reaming cutter housed vin said pocket and projecting therefrom, said reaming cutter, when viewed in cross section, presenting a curved edge merging into a at face on one side and into a flattened curve on the vother side, the

tangent of which flattened curve is at an acute angle to said flattened face.

5. A reaming drill comprising a head provided with a downwardly and outwardly inclined pocket, and a transversely toothed reaming cutter housed in said pocket, said reaming cutter, when viewed in cross s ection, presenting a sharply curved periphery pierglng into a flattened curve on the outer ace.

6.l A reaming drill comprising a head provided at its lower end with main cutting means and a separate and distinct reaming cutter housed in a' pocket at the side of the main cutting means and having a portion projecting therefrom, said reaming cutter presenting, when viewed in cross section, a sharply curved periphery merging into a iattened curve on the outer face.

7 A reaming drill comprising' a head provided at its'lower end with main cutting means, and having a downwardly and outwardly inclined pocket at the side of said cutting means ,open at its lower end, and a reaming cutter journaled in said pocket and projecting therefrom, said cutter having teeth on an oval shaped portion with the radii of the curve gradually decreasing toward the center of the drill, the major portion of the teeth reaming the hole formed by the drill.

In testimony whereof, I afliX my signature.

CLARENCE EDW'. vREED. 

